Rapid-release escapement for timing programmers

ABSTRACT

A rapid-release escapement according to the invention comprises a wheel having two rings of teeth, which is driven by a driving toothed wheel provided with an axial pin having a short nib and a long nib, opposite by 180*, the first of which engages the lower ring of teeth and the second of which engages both rings of teeth of said double toothed wheel. A stopping lever device is provided for stopping said double toothed wheel, said stopping lever device having two thin vertical ribs adapted to engage the teeth of said double toothed wheel.

States tet [1 1 RAPID-RELEASE ESCAPEMENT FOR TIMING PROGRAMMERS [76]Inventor: Renato Gazzani, via Maria 10C,

Frosinone, Italy 22 Filed: Feb. 16, 1972 21 Appl. No.: 226,910

[30] Foreign Application Priority Data Get. 30, 1973 PrimaryExaminer-Milton Kaufman Attorney-Marshall et al.

57 ABSTRACT A rapid-release escapement according to the inventioncomprises a wheel having two rings of teeth, which is driven by adriving toothed wheel provided with an axial pin having a short nib anda long nib, opposite by l80-, the first of which engages the lower ringof teeth and the second of which engages both rings of teeth of saiddouble toothed wheel. A stopping lever device is provided for stoppingsaid double toothed wheel, said stopping lever device having two thinvertical ribs adapted to engage the'teeth of said double toothed wheel.

8 Claims, 4 Drawing Figures RAPID-RELEASE ESCAPEMENT FOR TIMINGPROGRAMMERS BACKGROUND OF THE INVENTION This invention relates to arapid-release escapement, particularly for timing programmers, thatgenerates pulses of differential durations, especially adapted for usein linen washing machines, dish washing machines and like.

DESCRIPTION OF THE PRIOR ART An escapement for timing programmers isdescribed in US. Pat. No. 3,672,234; more particularly, said patentrelates to a rapid-release escapement, in which the time period betweenthe pulses, i. e. the step-by-step advancement of the excapement, is notidentical for each pulse. Namely, the time interval concerning a groupof pulses can be any integral multiple of the time interval concerninganother group of pulses.

The escapement according to the above patent is further characterized inthat the allotment of the individual pulses to the first or to thesecond group of pulses does not need to be in a specific sequentialorder; in fact, the desired succession order of pulses can bepreestablished at the designing stage.

In programmers according to the above cited patent an advancementarrangement is embodied which provides for the automatic stopping of theadvancement movement in any pre-established point of the cycle as wellas the restarting thereof after a fixed and preset time interval, bymeans of very simple device.

A further feature of the above excapement consists in that any overstepis prevented by means of a mechanicallycertain as well as inexpensivearrangement, said overstep being a common drawback in .rapidreleaseescapements of the prior art.

SUMMARY OF THE INVENTION The rapid-release escapement according to thisinvention sharesall the advantages of the escapement according to theabove previous patent; furthermore this invention has the same objectsand obtains the same results by using completely different means.

More particularly, this invention relates to a rapidrelease escapementprovided with a device that is adapted to prevent any overstep and thatworks upon the double toothed wheel generating the differential durationpulse sequences, so as to keep said wheel stationary during the timeintervals between each step and the next one. i

The above mentioned stopping device consists of a lever pivoted at anend and urged to rotate by means of a spring that applies its urgingforce to the central BRIEF DESCRIPTION OF THE DRAWINGS Further objectsand advantages of the escapement according to the invention will beevident fromthe following disclosure in connection with the attacheddrawings in which the preferred embodiment is shown and in which:

FIG. I is a partial view from above of the escapement according to theinvention;

FIG. 2 is a view from above of the escapement base member having thestopping device as well as the driving toothed wheel mounted thereon;

FIG. 3 is a view from below of the driving toothed wheel; and

' FIG. 4 is a view from below of the stopping device as well as of thedriving toothed wheel according to the invention.

DETAILED DESCRIPTION OF THE INVENTION The escapement according to thisinvention comprises a toothed wheel 10 provided with two rings of teeth,an upper ring and a lower ring, the teeth of which are so arranged as toprovide the desired sequences of pulses with differential durations. Thewheel 10 will be hereinafter designated with the term double toothedwheel," in order to point out that it has two series or rings of teeth.

The step-by-step advancement of the double toothed wheel 10 is carriedout by means of a driving toothed wheel 17. An axial pin 22 is providedon the toothed wheel 17 and has two nibs extending therealong, oppositeby to each other, namely a short nib 23, which can be engaged with thelower ring of teeth of the double toothed wheel 10, and a long nib 24,adapted to be engaged with the lower ring of teeth as well as with theupper ring of teeth of said wheel 10. In the time interval between astep of advancement and the next one, the nib 23 or 24 is stationary andengaged between the teeth of the double toothed wheel 10. In this mannerthe stopping of the double toothed wheel 10 is'effected and an overstepis prevented.

By overstep is meant in this specification an uncontrolled undesiredadvancement of the double toothed wheel 10 by more than one tooth.

The escapement according to this invention is different from theescapement as described in the above cited previous patent in the meansby which the stopping of said double toothed wheel 10 is effected and anoverstep is prevented. The arrangement by which said object is obtainedin this invention will be now more particularly described referring tothe drawings.

The double toothed wheel 10 receives its motion alternately from nibs 23and 24 of the driving toothed wheel 17, which receives in turn itsmotion from a transmission train, as described in the above citedpatent. As can be seen from FIG. 1, the main features of said drivingtoothed wheel 17 are said two nibs 23, 24 and the lower cam 18, providedwith two inversely symmetrical lobes. The rest and operative positionsof the driving toothed wheel 17 are determined by wound spring 19 actingalternately on the lobes of said cam 18.

The operation is designed such that, as can be seen from FIG. 1, in therest position, nibs 23 and 24 are not engaged between the teeth of saiddouble toothed wheel 10. At each rotation by an arc of 180 of thedriving toothed wheel 17, said nibs 23 and 24 alternately are engagedwith the teeth of said double toothed wheel 10, cause it to rotate byone tooth and then are disengaged therefrom.

The overstepping of said double toothed wheel 10 is prevented by thearrangement to be described. Said arrangement comprises a lever 50 thatis pivoted at an end on pin 51 fixed to the programmer housing. A smallcoiled, pressure spring 52 urges lever 50 to rotate; and applies itsurging force approximately on a central portion thereof. The other endof lever 50 has a catch 53 that, in its rest position, is abuttedagainst the pin 22 of the driving toothed wheel 17; it should be noted,however,.that the rest position of lever 50 is better defined by a stopmember 58.

Lever 50 has two thin vertical ribs 54 and 55 which are engaged with theteeth of said double toothed wheel said ribs 54 and 55 being arranged onsaid lever 50in a position corresponding to stop element 58, which isfixed to the base of the programmer housing. This arrangement is shownin FIG. 1.

Before describing the operation, reference will be made to FIG. 3, inwhich it is shown that the driving toothed wheel 17 has two drivingstuds 56 and 57 depending from cam 18. The profile of the above studs 56and 57 is extremely important, in fact it is to be pointed out that theradial surfaces of studs 56 and 57 have the profile of a circular arc,the central point of which is the center of said driving toothed wheel17.

Considering the rest position shown in the Figures, it is seen that saidribs 54, 55am engaged between the teeth of the double toothed wheel 10and said catch 53 contacts the leading edge of one of said driving studsprovided on said driving toothed wheel 17, e.g. stud 56 I in FIG. 4.

Referring to FIG. 4 it is seen that the driving toothed wheel 17 rotatesin a clockwise direction, whereby the catch 53 will be raised by stud56. The subsequent swing of lever 50 around pin 51, against the force ofsaid spring 52, causes the ribs54 and 55 to disengage from said doubletoothed wheel 10.

However, in this condition, said double toothed wheel 10' is not freelyrotatable, in view of the fact that it is in any case retainedstationary by resilient pawl 59 as described in the above mentionedpatent.

Continuing the clockwise rotation (in FIG. 4), the point of catch 53will slide along the radial surface of stud 56 and, owing to thecircular arc shape of said radial surface, said lever 50 will not beangularly moved any more. The positions of said dirving studs 56 and 57with respect to the lobes of cam 18 are such that, as soon as therelease of driving toothed wheel 17 occurs, and after the one stepadvancement of double toothed wheel 10 occurs as well, catch 53 snapspast the near edge of stud 56 resetting lever 50 to its rest position,under the pressure of spring 52. Vertical ribs 54 and 55 are positivelyengaged between the teeth of said double toothed wheel 10, therebypreventing any overstep.

It will be evident that, in view of the fact-that said double toothedwheel 10 has some teeth missing either from its lower ring or from itsupper ring of teeth, it is necessary that lever 50 be provided with atleasttwo ribs 54 and 55, adjacent to each other and displaced feom oneanother by the pitch of said rings of teeth of wheel 10.

The preferred embodiment of the stopping device according to thisinvention has been described hereinabove. However it should beunderstood that various 4 out departing from the scope of thisinvention.

What I claim is:

1. A rapid-release escapement for generating pulses with differentialdurations, comprising a wheel (10) having two rings of teeth, that isdriven by a driving toothed wheel (17), said driving toothedwheel (17)being provided with an axial pin (22) having a short nib (23) and a longnib (24), opposite to each other by the first of which engages the lowerring of teeth and the second of which engages both rings of teeth ofsaid double toothed wheel (10), characterized in that it comprises sstopping lever (50), provided with two thin vertical ribs (54, 55),adapted to be engaged between the teeth of said double toothed wheel(10); and further characterized in that said driving toothed wheel (17)has two depending studs (56, 57) operatively cooperating with a catch(53) provided on said stopping lever (50).

2. A rapid-release escapement as claimed in claim 1, characterized inthat said lever (50) is pivoted at an end on a pin (51) fixed to ahousing of the excapement, said lever being urged to rotate by means ofa coiled pressure spring (52), that applies its force on the centralportion of said lever (50).

3. A rapid-release escapement as claimed in claim 2, characterized inthat, in the rest position of the escapement, saidcatch (53) of lever(50) is abutted against the axial pin (22) of said driving toothed wheel(17) and said lever (50) is abutted against a stop member other by adistance identical to the pitch of said double toothed wheel (10).

6. A rapid-release escapement as claimedin claim 1, characterized inthat said driving toothed wheel (17) has two studs (56 57) for operationof said stopping lever (50).

7. A rapid-release excape'ment as claimed in claim 6,7 characterized inthat radial surfaces of said depending studs (56, 57) are shaped ascircular arcs, the central point of which is the central point of saiddriving toothed wheel (17).

8. A rapid-release escapement as claimed in claim 6, characterized inthat the relative positions of said depending studs (56, 57) are suchthat said lever (50), when operated, disengages said two ribs (54, 55)from the teeth of said double toothed wheel (10) so enabling itsstep-by-step advancement under the action of said driving toothed wheel(17) and thereafter said lever (50) snaps to its rest position forpreventing any overstep.

1. A rapid-release escapement for generating pulses with differentialdurations, comprising a wheel (10) having two rings of teeth, that isdriven by a driving toothed wheel (17), said driving toothed wheel (17)being provided with an axial pin (22) having a short nib (23) and a longnib (24), opposite to each other by 180*, the first of which engages thelower ring of teeth and the second of which engages both rings of teethof said double toothed wheel (10), characterized in that it comprises sstopping lever (50), provided with two thin vertical ribs (54, 55),adapted to be engaged between the teeth of said double toothed wheel(10); and further characterized in that said driving toothed wheel (17)has two depending studs (56, 57) operatively cooperating with a catch(53) provided on said stopping lever (50).
 2. A rapid-release escapementas claimed in claim 1, characterized in that said lever (50) is pivotedat an end on a pin (51) fixed to a housing of the escapement, said leverbeing urged to rotate by means of a coiled pressure spring (52), thatapplies its force on the central portion of said lever (50).
 3. Arapid-release escapement as claimed in claim 2, characterized in that,in the rest position of the escapement, said catch (53) of lever (50) isabutted against the axial pin (22) of said driving toothed wheel (17)and said lever (50) is abutted against a stop member (58) fixed to thehousing of said escapement.
 4. A rapid-release escapement as claimed inclaim 1, characterized in that sAid two vertical ribs (54, 55) are madein the body of said lever (50) in a position which is opposite to saidstop member (58) fixed to the housing of said escapement.
 5. Arapid-release escapement as claimed in claim 4, characterized in thatsaid vertical ribs (54, 55) made in the body of said lever (50) aredisplaced from each other by a distance identical to the pitch of saiddouble toothed wheel (10).
 6. A rapid-release escapement as claimed inclaim 1, characterized in that said driving toothed wheel (17) has twostuds 56, 57) for operation of said stopping lever (50).
 7. Arapid-release excapement as claimed in claim 6, characterized in thatradial surfaces of said depending studs (56, 57) are shaped as circulararcs, the central point of which is the central point of said drivingtoothed wheel (17).
 8. A rapid-release escapement as claimed in claim 6,characterized in that the relative positions of said depending studs(56, 57) are such that said lever (50), when operated, disengages saidtwo ribs (54, 55) from the teeth of said double toothed wheel (10) soenabling its step-by-step advancement under the action of said drivingtoothed wheel (17) and thereafter said lever (50) snaps to its restposition for preventing any overstep.